mtd: nand: Clarify Kconfig entry for software BCH ECC algorithm

There is no point in having two distinct entries, merge them and
rename the symbol for more clarity: MTD_NAND_ECC_SW_BCH

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
diff --git a/arch/mips/configs/db1xxx_defconfig b/arch/mips/configs/db1xxx_defconfig
index 34633b7..c5a2c6f 100644
--- a/arch/mips/configs/db1xxx_defconfig
+++ b/arch/mips/configs/db1xxx_defconfig
@@ -96,7 +96,7 @@
 CONFIG_MTD_M25P80=y
 CONFIG_MTD_SST25L=y
 CONFIG_MTD_NAND=y
-CONFIG_MTD_NAND_ECC_BCH=y
+CONFIG_MTD_NAND_ECC_SW_BCH=y
 CONFIG_MTD_NAND_AU1550=y
 CONFIG_MTD_NAND_PLATFORM=y
 CONFIG_MTD_SPI_NOR=y